product_list = [
    ("华为P30",4000),
    ("Mac pro",16000),
    ("Milk tea",20),
    ("crabs",88),
    ("bike",400),
    ("watch",40000),
    ("head first python",128),
    ("book",40)
]
shoopping_car = []
zhifubao = input("请输入支付宝的数字余额：")
#  购物车商品选择
if zhifubao.isdigit():
    zhifubao = int(zhifubao)
    while True:
        for item in product_list:
            print(product_list.index(item),item)
        choice = input("请选择你要购买的商品序号：")
        # 商品的选择
        if choice.isdigit():
            choice = int(choice)
            if choice >=0 and choice < 8:
                if zhifubao >= product_list[choice][1]:
                    zhifubao = zhifubao - product_list[choice][1]
                    shoopping_car.append(product_list[choice])
                    print("你把商品%s添加到了购物车，你的支付宝余额是%s："%(product_list[choice][0],zhifubao))
                else:
                    print("你的支付宝余额不足，请重新选择商品")
            else:
                print("商品列表里面没有这个商品，请重新选择一个商品")
        elif choice =="q":
            print("----购物车清单----")
            for item in shoopping_car:
                print(item)
            print("你的支付宝余额%s:"% zhifubao)
            break
        else:
            print("按q退出程序")
else:
    print("请输入数字金额")